Conventional toilet seat assemblies are well known in the prior art. A typical prior art toilet seat assembly comprises a generally oval toilet seat having a central opening and a matching toilet seat cover or lid. The seat and lid are connected by a compound hinge which is also secured to a toilet via two bolts extending through the hinge and holes in the toilet bowl. The holes are positioned at the rear of the toilet bowl, adjacent a water tank or other bowl-flushing mechanism, such that the lid and seat may be lifted and pivoted from the front of the bowl as may be desired. In two embodiments, the present invention assumes, and also preserves, this general arrangement.
It is further known that many users of toilet seat assemblies can have difficult in sitting from and then regaining a standing position as necessitated by toilet use. Persons having weak, infirm, or osteoarthritic legs and/or hips may be incapable of sitting and then regaining a standing position without external assistance.
It is known in the prior art to provide mechanisms which pivotably elevate a toilet seat mounted on a toilet by raising from the rear of the seat, causing a user to be gently propelled both upward and forward toward a standing position.
A general shortcoming of the prior art mechanisms is that they tend to be mechanically complex and thus expensive to manufacture and to purchase. In many instances, an assisted toilet seat may be needed for only a few weeks, as during recuperation of patients from knee- or hip-replacement surgery, and purchasing an expensive seat lift assembly cannot be justified.
Such prior art mechanisms typically employ electric or hydraulic motors with numerous levers and gears and complex mechanical or electric controls, which mechanisms may be accompanied by springs and may be intended to provide full mechanical lifting of a toilet user.
It is known in the art to incorporate gas springs in such lifting mechanisms.
U.S. Pat. Nos. 6,067,674 and 6,449,783 disclose a mechanism wherein a toilet seat is pivotably and non-removably attached at the front of a lifting mechanism. A pair of gas springs is attached to a toilet-mounted frame disposed on the top of the toilet bowl. The gas springs are mounted at the front of the lifting mechanism and extend generally rearwards of the toilet bowl, exerting a lifting force on the toilet seat at the rear of the toilet seat. In this arrangement, the gas springs have very poor mechanical advantage at the lifting point, particularly at the fully depressed seat position wherein the maximum lifting force is required. Further, because the seat is non-removably attached, cleaning the toilet bowl and the underside of the toilet seat is very difficult. Further, the gas springs are controlled by a user-activated switch.
U.S. Pat. No. 6,035,462 discloses a portable commode with spring-assisted lifting seat mounted on a lightweight self-supporting stand. The seat is hinged to the frame and a pair of pneumatic springs attached to the frame and the seat lift the seat to an elevated position. The springs yield under the body weight of the user to depress the seat to a lowered position. The springs which may be gas springs can be set at different positions on the seat to adjust for users of different body weights. A removable waste receptacle on the frame permits the commode to be used by itself, as at a bedside location, or over a conventional toilet bowl installation. This device is a self-contained commode having a full stand-alone frame and is not readily nor inexpensively adaptable for use with an existing toilet assembly. The full stand-alone frame is expensive to manufacture; and even when adapted to a toilet assembly, the frame rather than the toilet assembly must bear the full weight of the user.
U.S. Pat. No. 7,051,383 discloses a powered lift toilet seat comprising a toilet seat for sitting on, a back support for supporting a back of a person sitting on the toilet seat, and an actuator connected to the toilet seat and back support by a linkage device for raising and tilting the toilet seat and for moving the back support outwards, wherein the actuator is housed together with a toilet tank placed behind the back support, wherein the toilet tank has a recess for receiving therein the back support, and wherein the recess is concave and a rear portion of the back support that is received in the recess is convex. The actuator may include a gas spring. The actuator is housed in an integral toilet tank assembly such that the invention is not readily nor inexpensively adaptable to an existing toilet assembly and requires significant disassembly of an existing toilet.
What is needed in the art is a gas spring lift assisted toilet seat assembly that has few components, is simple to assemble and install, is affixed to a toilet bowl via the original seat bolt holes, and has excellent mechanical advantage for lifting a toilet seat from a seated-user position.
It is a principal object of the present invention to lift a toilet assembly user simply and inexpensively from a sitting position toward a standing position.